The AGS (American Gem Society) grade scale ranges from 0 (Ideal), representing the highest quality, to 10 (Poor), indicating the lowest quality.
Understanding the AGS Grading System
The American Gem Society (AGS) is highly respected in the gemological world, particularly for its rigorous and comprehensive diamond grading system, with a significant emphasis on cut quality. Unlike systems that might prioritize only color and clarity, AGS meticulously evaluates how a diamond's facets interact with light, which directly influences its brilliance, fire, and scintillation.
The AGS Grade Scale in Detail
AGS employs a numerical grading system where the best grades are represented by the lowest numbers. This scale extends from 0 to 10, with specific numerical ranges corresponding to different quality designations for various diamond characteristics, most notably cut.
Cut Grade Evaluation
For the cut grade, which is a hallmark of AGS certification, the assessment typically breaks down into three primary categories. Beyond evaluating the diamond from a direct face-up view, AGS also considers how the stone performs when tilted, meticulously examining its optics and light return from various angles to ensure a complete evaluation of its light performance.
The AGS grade scale is summarized as follows:
AGS Grade | Description |
---|---|
0 | Ideal (The highest grade, representing exceptional light performance) |
1 | Excellent |
2 | Very Good |
3-4 | Good |
5-7 | Fair |
8-10 | Poor (The lowest grade, indicating significant issues with light interaction) |
This system allows consumers and professionals to precisely understand a diamond's quality, especially its cut, which is crucial for a diamond's overall beauty and sparkle.